This invention relates to a system for containing and thereby preventing the leaking of solution from an iontophoretic bioelectrode or the like.
Iontophoretic bioelectrodes, used in place of hypodermic needles to inject drugs and medication into a person's skin or tissue, typically include a pouch or similar enclosure formed with a wettable barrier or a microporous membrane on one side thereof. See, for example, U.S. Pat. Nos. 4,250,878, 4,419,092 and 4,477,971. A medication solution containing ions to be delivered into the person's skin or tissue is injected into the pouch. When the wettable barrier or membrane is placed against a person's skin and an electric current is supplied to the solution, the ions are caused to migrate from the solution, through the wettable barrier or membrane, and into the skin.
The membrane is adapted to prevent the flow therethrough of solution while allowing movement therethrough of ions. The membrane thus prevents leakage of solution during and after use, and is thus substantially "mess" free. The wettable barrier, on the other hand, although less costly than the membrane, does not prevent leakage of solution and so must be covered until time of use. After use and removal of the pouch from the skin, unused solution would remain on the skin, drip or run on the skin, possibly stain a patient's clothing, and generally cause a mess. It would thus be desirable to somehow contain this solution and prevent it from escaping from the pouch, without requiring use of expensive membranes.